Condensed Consolidated Income Statements Of Income and Comprehensive Income (Parenthetical) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Oct. 31, 2020	Aug. 01, 2020	May 02, 2020	Nov. 02, 2019	Aug. 03, 2019	May 04, 2019	Oct. 31, 2020	Nov. 02, 2019
OtherComprehensiveIncomeLossTaxParentheticalDisclosuresAbstract
Tax Effect of Unrealized Gains (Losses) On Available-For-Sale Securities	$ (85)	$ 146	$ (90)	$ (8)	$ 262	$ 126	$ (29)	$ 380

Amount, before adjustment, of tax expense (benefit) for unrealized holding gain (loss) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale). Excludes tax expense (benefit) for unrealized gain (loss) on investment in debt security measured at amortized cost (held-to-maturity) from transfer to available-for-sale.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section 45
-Paragraph 12
-URI http://asc.fasb.org/extlink&oid=121641772&loc=d3e640-108580

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section 45
-Paragraph 10A
-Subparagraph (f)
-URI http://asc.fasb.org/extlink&oid=121641772&loc=SL7669646-108580

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration